Abstract

Background

Eurytrema pancreaticum is one of the most common flukes, which mainly infects ruminants globally and infects
human beings accidentally; causing eurytremiasis that has high veterinary and economic
importance. MicroRNAs (miRNAs) are small non-coding RNAs and are now considered as
a key mechanism of gene regulation at the post-transcription level.

Methods

Results

By using the genome of the closely-related species Schistosoma japonicum as reference, we obtained 27 miRNA candidates out of 16.45 million raw sequencing
reads, with 13 of them found as known miRNAs in S. japonicum and/or S. mansoni, and the remaining 14 miRNAs were considered as novel. Five out of the 13 known miRNAs
coming from one family named as sja-miR-2, including family members from miR-2a to
miR-2e. Targets of 19 miRNAs were successfully predicated out of the 17401 mRNA and
EST non-redundant sequences of S. japonicum. It was found that a significant high number of targets were related to “chch domain-containing
protein mitochondrial precursor” (n = 29), “small subunit ribosomal protein s30e”
(n = 21), and “insulin-induced gene 1 protein” (n = 9). Besides, “egg protein cp3842”
(n = 2), “fumarate hydratase” (n = 2), “ubiquitin-conjugating enzyme” (n = 2), and
“sperm-associated antigen 6” (n = 1) were also found as targets of the miRNAs of E. pancreaticum.

Conclusions

The present study represents the first global characterization of E. pancreaticum miRNAs, which provides novel resources for a better understanding of the parasite,
which, in turn, has implications for the effective control of the disease it causes.